For inspection of electrical conduction of an electronic device including IC or LSI or the like, a socket for inspection is used with a connection terminal pressed against an electrode of the electric device to take out an electrical signal from the electrode through the connection terminal. A connector for installation is used with a connection terminal pressed against a land electrode of an electric device to maintain electrical conduction through the connection terminal. The inspection socket and the installation connector are provided with the number of connection terminals corresponding to the number of electrodes of an electronic device for connection. As electrodes of an electric device increase in density, the connection terminals of the inspection socket and the installation connector are also required to increase in density.
As the connection terminal, for example, a connection terminal for BGA (Ball Grid Array) is known which has a planar spiral shape before connection to a ball-shaped electrode and, due to the connection to the ball-shaped electrode, the spiral deforms in accordance with the shape of the ball-shaped electrode (see Patent Document 1). The spiral terminal can address the densification of electrodes and has high connection reliability since it can ensure electrical conduction in accordance with the shape of a ball-shaped electrode.
A spiral terminal for inspection includes a volute terminal which has a spiral spring that is lower at its perimeter and higher toward its central portion, for example (see Patent Document 2). When a conical probe portion disposed at the end of the volute terminal is pressed against a planar electrode of a body to be inspected, it is ensured that the conical probe portion is connected to the planar electrode of the body to be inspected due to urging force of the spring.
Patent Document 1: Japanese Patent Laying-Open No. 2002-175859
Patent Document 2: Japanese Patent Laying-Open No. 2001-235486